Processing of task-irrelevant natural scenes in social anxiety

In this study, by manipulating perceptual load, we investigated whether socially anxious people process task-irrelevant, non-emotional, natural scenes. When attention was directed to letters and perceptual load was low, task-irrelevant natural scenes were processed, as evidenced by repetition priming effects, in both high and low socially anxious people. In the high perceptual load condition, repetition-priming effects decreased in participants with low social anxiety, but not in those with high social anxiety. The results were the same when attention was directed to pictures of animals: even in the high perceptual load condition, high socially anxious participants processed task-irrelevant natural scenes, as evidenced by flanker effects. However, when attention was directed to pictures of people, task-irrelevant natural scenes were not processed by participants in either anxiety group, regardless of perceptual load. These results suggest that high socially anxious individuals could not inhibit task-irrelevant natural scenes under conditions of high perceptual load, except when attention was focused on people.     

The effects of cognitive activity and perceptual details on speech source monitoring

Our purpose in this study was to investigate the effects of cognitive operations and perceptual details on speech source monitoring. In Phase 1, correctly spelled words and anagrams were presented in Expt 1. Words were read aloud by participants, by a same‐sex voice, or by an opposite‐sex voice. Immediately after Phase 1, in Phase 2, participants were asked whether each word had been read aloud by the participants themselves, by a same‐sex voice, or by an opposite‐sex voice. Source discrimination between own speech and that produced by a same‐sex voice was poorer than between own speech and an opposite‐sex voice. In addition, misattribution of the speech of another to one's self increased as the level of cognitive effort required for the task increased. In Expt 2, misattributions to same‐sex voice were assigned ‘know’ responses more frequently and misattributions to one's self were assigned ‘remember’ responses more frequently. These results suggest that qualitative characteristics such as perceptual detail and cognitive operations are differentially influencing misattributions to the self and those to same‐sex voices.     

Involvement of IP3 receptors in LTP and LTD induction in guinea pig hippocampal CA1 neurons

The role of inositol 1, 4, 5-trisphosphate receptors (IP3Rs) in long-term potentiation (LTP) and long-term depression (LTD) was studied in CA1 neurons in guinea pig hippocampal slices. In standard solution, short tetanic stimulation consisting of 15 pulses at 100 Hz induced LTP, while three short trains of low-frequency stimulation (LFS; 200 pulses at 1 Hz) at 18-min intervals or one long train of LFS (1000 pulses at 1 Hz) induced stable LTD in both the slope of the field EPSP (S-EPSP) and the amplitude of the population spike (A-PS). Bath application of 2-aminoethoxydiphenyl borate (2-APB), an IP3R antagonist, or of alpha-methyl-4-carboxyphenylglycine (MCPG), a wide-spectrum metabotropic glutamate receptor antagonist, during weak tetanic stimulation significantly increased the magnitude of the LTP in both the S-EPSP and A-PS. Three short trains of LFS or one long train of LFS delivered in the presence of 2-APB or MCPG did not induce LTD, but elicited LTP. Based on these results, we conclude that, in hippocampal CA1 neurons, IP3Rs play an important role in synaptic plasticity by attenuating LTP and facilitating LTD.     

How do Rumination and Social Problem Solving Intensify Depression? A Longitudinal Study

In order to examine how rumination and social problem solving intensify depression, the present study investigated longitudinal associations among each dimension of rumination and social problem solving and evaluated aspects of these constructs that predicted subsequent depression. A three-wave longitudinal study, with an interval of 4 weeks between waves, was conducted. Japanese university students completed the Beck Depression Inventory-Second Edition, Ruminative Responses Scale, Social Problem-Solving Inventory-Revised Short Version, and Interpersonal Stress Event Scale on three occasions 4 weeks apart (n = 284 at Time 1, 198 at Time 2, 165 at Time 3). Linear mixed models were analyzed to test whether each variable predicted subsequent depression, rumination, and each dimension of social problem solving. Rumination and negative problem orientation demonstrated a mutually enhancing relationship. Because these two variables were not associated with interpersonal conflict during the subsequent 4 weeks, rumination and negative problem orientation appear to strengthen each other without environmental change. Rumination and impulsivity/carelessness style were associated with subsequent depressive symptoms, after controlling for the effect of initial depression. Because rumination and impulsivity/carelessness style were not concurrently and longitudinally associated with each other, rumination and impulsive/careless problem solving style appear to be independent processes that serve to intensify depression.     

Need for Cognition Promotes Adaptive Style of Self‐Focusing with the Mediation of Effortful Control

Previous studies have indicated that “need for cognition” (NfC), which is the tendency to enjoy effortful cognitive activity, affects various cognitive processes and behaviors. However, the effects of NfC on mental adaptation have not been investigated. According to previous studies, it can be hypothesized that NfC decreases maladaptive self‐focusing, which is called self‐rumination, through increasing effortful control (EC); therefore, we hypothesized that NfC would indirectly inhibit self‐rumination through the mediation of EC. As we expected, the results of a cross‐sectional questionnaire study with 152 undergraduate participants indicated a negative indirect association between NfC and self‐rumination through the mediation of EC. Secondarily, the present results revealed a direct positive association between NfC and adaptive type of self‐focusing, which is called self‐reflection. The present study is the first to propose the possible contribution of NfC to mental health through decreasing self‐rumination and increasing self‐reflection.     

Diurnal variation in rumination

The present study investigated the daily fluctuation of ruminative thinking and its individual differences by using the experience sampling method. Participants recorded their thought contents and negative affect eight times a day for a week at semirandom intervals. High-trait ruminators showed high levels of self-focus, unpleasantness, and uncontrollability in their thoughts over the sampling course. These variables were interacted to predict the levels of concurrent negative affect: Self-focus was strongly associated with increased levels of negative affect when the thought was highly unpleasant and uncontrollable. A composite measure of rumination, including self-focus, unpleasantness, and uncontrollability, exhibited diurnal variation, which was assimilated by a quadratic function of time of day. However, there were differences in the estimated parameters of diurnal trajectories between high and low levels of depression, which indicated that individuals with higher levels of depression are more likely to engage in rumination in the evening, not in the morning, than those with lower levels of depression. These findings suggest that rumination in the evening would play an important role in the exacerbation and maintenance of depression.     

Exogenous attention to angry faces in social anxiety: a perceptual accuracy approach

We investigated the interaction between endogenous and exogenous attention for the processing of emotional stimuli in individuals with high social anxiety using accuracy rates. Following the presentation of an endogenous cue at the centre, exogenous cues (i.e., angry and neutral faces) were presented at peripheral locations. Subsequently, non-emotional masked targets were presented, and the participants were instructed to discriminate between the targets. With respect to exogenous attention, high socially anxious people exhibited higher accuracy when the angry face and target appeared on the same side than when they appeared on different sides, whereas low socially anxious people did not exhibit such effects. On the other hand, different abilities of endogenous attention were not observed between high and low socially anxious people. These results suggest that exogenous attention is biased towards threat in high socially anxious people.     

Rubber hand illusion, empathy, and schizotypal experiences in terms of self-other representations

When participants observed a rubber hand being touched, their sense of touch was activated (rubber hand illusion: RHI). While this illusion might be caused by multi-modal integration, it may also be related to empathic function, which enables us to simulate the observed information. We examined individual differences in the RHI, including empathic and schizotypal personality traits, as previous research had suggested that schizophrenic patients would be more subject to the RHI. The results indicated that people who experience a stronger RHI might have stronger empathic and schizotypal personalites simultaneously. We discussed these relationships in terms of self-other representations.     

Repeated short presentations of morphed facial expressions change recognition and evaluation of facial expressions

This study investigated whether sensitivity to and evaluation of facial expressions varied with repeated exposure to non-prototypical facial expressions for a short presentation time. A morphed facial expression was presented for 500 ms repeatedly, and participants were required to indicate whether each facial expression was happy or angry. We manipulated the distribution of presentations of the morphed facial expressions for each facial stimulus. Some of the individuals depicted in the facial stimuli expressed anger frequently (i.e., anger-prone individuals), while the others expressed happiness frequently (i.e., happiness-prone individuals). After being exposed to the faces of anger-prone individuals, the participants became less sensitive to those individuals’ angry faces. Further, after being exposed to the faces of happiness-prone individuals, the participants became less sensitive to those individuals’ happy faces. We also found a relative increase in the social desirability of happiness-prone individuals after exposure to the facial stimuli.